A metal oxide semiconductor field effect transistor (MOSFET) which includes lightly doped drain (LDD) regions includes a capacitance formed between a gate electrode and LDD regions on source and drain sides of the MOSFET. Spacer layers formed over sidewalls of the gate electrode act as an insulating material between the conductive features of the gate electrode and the LDD regions. A first capacitor Cgs is formed between the gate electrode and the LDD region on the source side of the MOSFET, and a second capacitor Cgd is formed between the gate electrode and the LDD region on the drain side of the MOSFET.
An amount of capacitance in the first capacitor Cgs and the second capacitor Cgd is determined by a dopant concentration in the LDD regions and by an amount of overlap of the LDD regions with the gate electrode. As the dopant concentration of the LDD regions increases, a conductivity of the LDD regions increases resulting in an increase in capacitance.